I know people who have done both and succeded. I did the weight watchers and lost a stone n a half. I did it slowly and sensibly. W.W is good as its a well balanced diet with all the nutrients the body needs. Slimmers world is also good, however, with the red/green days its sometimes can lack certain nutrients and me having a busy job/lifestyle I found that w.w suited me best.mIts all about changing habits and i agree its so hard, i still struggle now, but its worth it when you start to see results